Please select permitted totals variant for release

What causes this issue?

You selected the function <LS>Save invoice release</>. This function is
only possible with the following totals variants:
Document totals

How to fix this error?

Change the totals variant:
RESET N1.
Select <LS>Goto</> --> <LS>Back</> to exit the totals display.
Make sure that the cursor is not on an item line, and then select
<LS>Edit</> --> <LS>Total</>.
A window is displayed in which you select the totals variant. Select
one of the variants: <LS>Document number totals</>. You proceed to the
relevant totals display from which you can now release the invoice
items.

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